<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>

<body>
    <script>
        //Es6允许给函数参数赋初始值
        //1.形参初始值,具有默认值的参数，一般位置靠后(潜规则)
        function add(a, b, c = 10) {
            return a + b + c;
        }
        let result = add(1, 2);
        console.log(result);

        //与解构赋值结合,第一个参数有值，对象里面没有，则用默认值
        function connect({ host, username, password, port }) {
            console.log(host);
            console.log(username);
            console.log(password);
            console.log(port);

        }
        connect({
            host: 'localhost',
            username: 'root',
            password: 'root',
            port: 3306
        })
    </script>
</body>

</html>